2 * This code is derived from uClibc (original license follows).
3 * https://git.uclibc.org/uClibc/tree/utils/mmap-windows.c
5 /* mmap() replacement for Windows
7 * Author: Mike Frysinger <vapier@gentoo.org>
8 * Placed into the public domain
12 * CreateFileMapping: http://msdn.microsoft.com/en-us/library/aa366537(VS.85).aspx
13 * CloseHandle: http://msdn.microsoft.com/en-us/library/ms724211(VS.85).aspx
14 * MapViewOfFile: http://msdn.microsoft.com/en-us/library/aa366761(VS.85).aspx
15 * UnmapViewOfFile: http://msdn.microsoft.com/en-us/library/aa366882(VS.85).aspx
20 #include "WindowsMMap.h"
22 #define WIN32_LEAN_AND_MEAN
25 #include "InstrProfiling.h"
27 COMPILER_RT_VISIBILITY
28 void *mmap(void *start, size_t length, int prot, int flags, int fd, off_t offset)
30 if (prot & ~(PROT_READ | PROT_WRITE | PROT_EXEC))
33 if (!(flags & MAP_ANON) || offset)
35 } else if (flags & MAP_ANON)
39 if (prot & PROT_WRITE) {
41 flProtect = PAGE_EXECUTE_READWRITE;
43 flProtect = PAGE_READWRITE;
44 } else if (prot & PROT_EXEC) {
46 flProtect = PAGE_EXECUTE_READ;
47 else if (prot & PROT_EXEC)
48 flProtect = PAGE_EXECUTE;
50 flProtect = PAGE_READONLY;
52 off_t end = length + offset;
55 mmap_fd = INVALID_HANDLE_VALUE;
57 mmap_fd = (HANDLE)_get_osfhandle(fd);
58 h = CreateFileMapping(mmap_fd, NULL, flProtect, DWORD_HI(end), DWORD_LO(end), NULL);
62 DWORD dwDesiredAccess;
63 if (prot & PROT_WRITE)
64 dwDesiredAccess = FILE_MAP_WRITE;
66 dwDesiredAccess = FILE_MAP_READ;
68 dwDesiredAccess |= FILE_MAP_EXECUTE;
69 if (flags & MAP_PRIVATE)
70 dwDesiredAccess |= FILE_MAP_COPY;
71 void *ret = MapViewOfFile(h, dwDesiredAccess, DWORD_HI(offset), DWORD_LO(offset), length);
79 COMPILER_RT_VISIBILITY
80 void munmap(void *addr, size_t length)
82 UnmapViewOfFile(addr);
83 /* ruh-ro, we leaked handle from CreateFileMapping() ... */
86 COMPILER_RT_VISIBILITY
87 int msync(void *addr, size_t length, int flags)
89 if (flags & MS_INVALIDATE)
90 return -1; /* Not supported. */
92 /* Exactly one of MS_ASYNC or MS_SYNC must be specified. */
93 switch (flags & (MS_ASYNC | MS_SYNC)) {
101 if (!FlushViewOfFile(addr, length))
104 if (flags & MS_SYNC) {
105 /* FIXME: No longer have access to handle from CreateFileMapping(). */
107 * if (!FlushFileBuffers(h))
115 COMPILER_RT_VISIBILITY
116 int lock(HANDLE handle, DWORD lockType, BOOL blocking) {
117 DWORD flags = lockType;
119 flags |= LOCKFILE_FAIL_IMMEDIATELY;
121 OVERLAPPED overlapped;
122 ZeroMemory(&overlapped, sizeof(OVERLAPPED));
123 overlapped.hEvent = CreateEvent(NULL, FALSE, FALSE, NULL);
124 BOOL result = LockFileEx(handle, flags, 0, MAXDWORD, MAXDWORD, &overlapped);
126 DWORD dw = GetLastError();
128 // In non-blocking mode, return an error if the file is locked.
129 if (!blocking && dw == ERROR_LOCK_VIOLATION)
130 return -1; // EWOULDBLOCK
132 // If the error is ERROR_IO_PENDING, we need to wait until the operation
133 // finishes. Otherwise, we return an error.
134 if (dw != ERROR_IO_PENDING)
138 if (!GetOverlappedResult(handle, &overlapped, &dwNumBytes, TRUE))
145 COMPILER_RT_VISIBILITY
146 int flock(int fd, int operation) {
147 HANDLE handle = (HANDLE)_get_osfhandle(fd);
148 if (handle == INVALID_HANDLE_VALUE)
151 BOOL blocking = (operation & LOCK_NB) == 0;
152 int op = operation & ~LOCK_NB;
156 return lock(handle, LOCKFILE_EXCLUSIVE_LOCK, blocking);
159 return lock(handle, 0, blocking);
162 if (!UnlockFile(handle, 0, 0, MAXDWORD, MAXDWORD))